Granted Patent
Utility
US 4,239,882 · App. 05/609,964
Process for producing polyester
Inventors:
Tsuneo Kimura, Katsuhisa Kohyama, Takehiro Okada, Katsuyuki Sakata
Patented Case
View Patent ↗
Granted: Dec 16, 1980
Filed: Sep 3, 1975
Inventors
Tsuneo Kimura
Katsuhisa Kohyama
Takehiro Okada
Katsuyuki Sakata
Assignee (at issue)
Mitsubishi Chemical Industries, Ltd.
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.